This invention relates to a connector, such as a waterproof connector, in which a wire, connected to a terminal received in a chamber in a connector housing, is sealed by a rubber plug.
A connector of the type described is disclosed in Japanese Patent Publication No. 9-106847A, this connector being shown in FIGS. 7 to 10. As shown in FIGS. 7 and 8, this connector 1 comprises a housing 2, having a pair of right and left tubular chambers 3 for respectively receiving terminals 9 each press-clamping a wire 7 and a rubber plug 8, a box-shaped fixture 5 fitted on outer faces of peripheral walls of the two tubular chambers 3 at front end portions thereof, and an annular waterproof packing 6 fitted on the outer faces of the peripheral walls of the two tubular chambers 3 at rear end portions thereof. A notch 3a is formed in a central portion of the upper front portion of the peripheral wall of each tubular chamber 3, and a cantilevered flexible arm 4 for retaining the terminal 9 is formed so as to extend in this notch portion 3a. 
For assembling the connector 1, a pair of small projections 5b, formed respectively on inner faces of right and left side walls of the fixture 5, are fitted respectively in front ends of slots 3b formed respectively in the side walls of the two tubular chambers 3 as shown in FIGS. 8 and 9, so that the fixture 5 is provisionally fitted (provisionally retained) on the front end portions of the two tubular chambers 3 each of which is disposed forwardly of a region where the flexible arm 4 can be elastically deformed. Then, the terminals 9, each press-clamping the wire 7 and the rubber plug 8, are inserted respectively into the tubular chambers 3 from the rear side of the housing 2 as shown in FIG. 8, so that each terminal 9 is primarily retained in the tubular chamber 3 by the flexible arm 4. Then, when the fixture 5 is further pushed as shown in FIG. 10, projections 5a, formed on an inner face of an upper wall of the fixture 5, are fitted respectively into front ends of the notches 3a, and are disposed respectively at the regions of elastic deformation of the flexible arms 4, so that the fixture 5 is completely fitted (completely retained) on the pair of tubular chambers 3. As a result, the elastic deformation of each flexible arm 4 is prevented, so that each terminal 9 is retained in a double manner.
In the conventional connector 1, each terminal 9 is received in the corresponding tubular chamber 3 in the housing 2, and is retained by the elastic arm 4. When vibrations, applied to the housing 2, are transmitted to each terminal 9, the vibrations are absorbed only by the rubber plug 8 press-clamped to a rear portion of the terminal 9. Therefore vibrations, acting on a terminal body of the terminal 9, could not be absorbed only by the rubber plug 8, and when the connector 1 is mounted, for example, on a vehicle, a portion of contact of the terminal 9 with a mating terminal is worn by the vibrations, so that the reliability (contact reliability) of the terminal 9 becomes low.
Therefore, this invention has been made in order to solve the above problem, and an object of the invention is to provide a connector in which vibrations, transmitted to a terminal, are positively absorbed by an elastic member, interposed between and held in intimate contact with an outer housing and an inner housing, thereby enhancing a contact reliability of the terminal.
In order to achieve the above object, according to the present invention, there is provided a connector, comprising:
a terminal;
a first elastic member, provided at a rear end portion of the terminal;
an inner housing, including an inner peripheral wall which defines a first chamber for retaining at least a front end portion of the terminal, and an outer peripheral wall extending parallel with the inner peripheral wall while defining a gap therebetween;
an outer housing, including a peripheral wall which defines a second chamber for retaining at least first elastic member; and
a second elastic member, fitted around the peripheral wall of the outer housing,
wherein the inner housing and the outer housing are engaged with each other such that a front end portion of the peripheral wall of the outer housing is inserted into the gap formed between the inner peripheral wall and the outer peripheral wall of the inner housing, and such that a rear end face of the outer peripheral wall of the inner housing is brought into an intimate contact with the second elastic member.
In this configuration, in addition to the first elastic member fitted in the outer housing, vibrations, applied to the outer housing, are absorbed by the second elastic member, interposed between and held in intimate contact with the inner housing and the outer housing, and therefore will not be transmitted to the terminal. Therefore, when the connector is mounted, for example, on a vehicle, that portion of contact of the terminal with a mating terminal will not be subjected to wear, so that the contact reliability of the terminal is enhanced.
Preferably, the inner housing and the outer housing are engaged with each other such that a clearance is formed between an outer face of the inner peripheral wall of the inner housing and an inner face of the peripheral wall of the outer housing.
In this configuration, since the vibrations applied to the outer housing can be further prevented from being transmitted to the terminal, the contact reliability of the terminal is further enhanced.